This invention relates to the art of vacuum cleaners, and more particularly to a vacuum cleaner attachment for converting a dry vacuum cleaner into a wet vacuum cleaner for picking up liquid off a surface.
The present invention relates to converting a traditional dry vacuum cleaner into a wet vacuum cleaner. Dry vacuum cleaners are known in the art and are generally shown in Nakai 6,243,915; and Wright 6,003,196. Nakai discloses a dry vacuum cleaner which utilizes a bag type retention area and is incorporated by reference herein as background information. Wright teaches the use of cyclonic action to separate the particles from the air in a fluid stream. Wright is also incorporated by reference as background information.
It is, of course, well known that a vacuum source can be used to remove either particles or liquids from a surface and deposit the same in a designated location. In this respect, an electric motor typically drives an impeller which creates a vacuum that is then directed to the surface, wherein the liquid and/or particles are drawn away from the surface in a fluid stream toward the vacuum source. Eventually, the fluid stream is directed into a designated retention area that is designed to separate the particles and/or liquids from any air in the fluid stream. The air is then allowed to escape through a designated exhaust opening. In order to retain the particles, some form of filter arrangement is utilized which is positioned in the fluid stream either before or after the vacuum source. No matter whether the vacuum source is before or after the filter arrangement of the retention area, the motor must be protected from the particles and/or liquids traveling in the fluid stream to prevent damage. Further, the air in the fluid stream is typically utilized to cool the motor. The way in which the motor and the impeller of the vacuum source are protected from damage is dependent on whether the vacuum system is designed to remove particles or liquid from a surface and the position of the vacuum source in the fluid stream.
Not all vacuum systems are suitable for removing both particles and liquids from a surface due to the differences in separating liquids from air and separating particles form air. With respect to removing particles from a surface, the fluid stream consist mostly of air and the particles to be removed. The retention area is often a fiber based system which separates the particles from the air in the fluid stream by preventing the particles from passing through the fibers while allowing the air to freely pass through to an exhaust opening. In many cases, the fiber material is a porous bag which allows the air to escape while retaining a majority of the particles in a conveniently disposable retention area. Another type of particle retention area utilizes cyclonic airflow to separate the particles from the air in the fluid stream. Wright discloses the use of cyclonic separation. While these methods are effective in removing particles from an air stream, moisture in the air stream can have adverse effects on all portions of the vacuum system. In this respect, entry of moisture into the bag can cause mold to form, which can then be released into the surrounding air during subsequent uses. Further, the moisture can cause clumping or clogging of the pores in the bag, reducing the effectiveness of the particle removal and putting undue strain on the motor of the vacuum source. Further, moisture in the bag can eventually leak into the housing of the vacuum cleaner since the bag is not designed to retain moisture. With respect to cyclonic separation, moisture can reduce the cyclonic action and can produce mold and/or clog the exhaust opening. Another problem relates to the housing and motor of the vacuum cleaner. As stated above, the air from the fluid stream is typically used to cool the motor and therefore moisture in the fluid stream should be minimized. With respect to the housing and other structural components, metal is often used for many components within the vacuum cleaner which can rust if liquids are introduced into the fluid stream.
As a result, most vacuum cleaners are either designed for removing liquids from a surface or removing particles from a surface. Even if a vacuum is designed to remove both particles and liquids, the retention area must be cleaned immediately after the vacuum cleaner is used to prevent the particles and liquids from comingling and forming a hard solid residue which is difficult to remove or which can produce molds or other bacteria Further, the vacuum source must be designed to handle both moisture and particles in the fluid stream. This usually involves moisture protection for the motor and at least some form of particle filter to protect the motor and impellers from the particles in the fluid stream.
In accordance with the present invention, an attachment for a vacuum cleaner is provided which advantageously enables a vacuum cleaner designed to pick up dry particles to be converted into a wet vacuum cleaner which can pick up liquids and retain the same without interfering with the retention of the dry particles or adversely affecting the vacuum source. More particularly, the vacuum cleaner attachment according to the present invention can be easily connected to a vacuum source of a dry vacuum cleaner and utilize the vacuum source of the vacuum cleaner to remove liquid from a surface with out introducing the liquid into the primary air stream within of the dry vacuum cleaner.
The foregoing is achieved by utilizing the air stream of the vacuum cleaner to produce a second, independent vacuum source. Preferably, the exhaust of the primary air stream, which has already passed the motor and the particle retention area, is used to produce the secondary, independent vacuum source which draws the liquid from the surface into a reservoir separate from the particle retention area of the vacuum cleaner. If the attachment is connected to the exhaust opening, moisture cannot enter the primary air stream within the vacuum cleaner and therefore cannot affect the motor or the particle retention area of the vacuum cleaner. If the attachment is connected to the intake, the amount of moisture entering the primary air stream is significantly reduced. In addition, by utilizing a separate reservoir for the liquid picked up from the surface, the liquid can be maintained in a reservoir designed for liquid retention which can be easily drained after use.
It is accordingly an outstanding object of the present invention to provide a vacuum cleaner attachment for converting a dry vacuum cleaner into a wet vacuum cleaner which utilizes the air stream of a vacuum source of a dry vacuum cleaner to produce a secondary vacuum source which removes the liquids from the surface without moisture entering into the primary air stream within the vacuum cleaner.
Another object is the provision of a vacuum cleaner attachment according to the present invention that can be easily and quickly attached to a dry vacuum cleaner.
A further object of the present invention is the provision of a vacuum cleaner attachment of the foregoing character which retains the liquid in a retention area separate from the retention area for the dry particles.
Still another object of the present invention is the provision of a vacuum cleaner attachment of the foregoing character which requires only a minimal number of moving parts.
Yet another object of the present invention is the provision of a vacuum cleaner attachment of the foregoing character which is compact and light weight for easy use thereof.
Still a further object of the present invention is the provision of a vacuum cleaner attachment of the foregoing character which is cost effective to manufacture.